Worried about changing medicines?

Advice and reassurance when your asthma medicines or inhalers have changed

Health advice > Inhalers, medicines and treatments > Changing medicines

Get answers to your questions about changing asthma medicines, including how long it will take to see the benefits, what to do if symptoms don’t improve, and how to safely switch to a low carbon, greener inhaler. 

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Is it safe to change medicines and inhalers?

It is safe to try a change of medicine or inhaler device if your GP or asthma nurse has recommended it. In fact, it can make a difference to how well you manage your asthma and stick to your medicine routine.

The most important things are:

  • your asthma medicines protect you from asthma attacks and symptoms
  • you have an inhaler you can use easily and well
  • you’re happy with your inhaler.

Check with your GP or asthma nurse when you should stop taking your existing medicine and start your new one.

If you’ve been prescribed the same medicine, but at a different dose, you’ll probably be asked to start this straight away.

Whenever you start a new medicine you should have a follow up appointment with your GP or asthma nurse six to eight weeks later, to see how you’re getting on with it.

Get an appointment sooner than this if you notice symptoms getting worse, or that you need to use your reliever inhaler more often. 

When can I start taking my new medicine?

Whenever you’re given a new medicine, check with your GP or asthma nurse when you should stop taking your existing medicine and start your new one.

If you’ve been prescribed the same medicine, but at a different dose, you’ll probably be asked to start this straight away.

If you’ve been switched to a new inhaler, for example from a metered dose inhaler (MDI) to a more environmentally-friendly dry powder inhaler (DPI), make sure your asthma is well-controlled before changing to your new inhaler. If you’re not sure or don’t feel confident that your asthma is well controlled, talk to your GP or asthma nurse.

What’s the right technique for my new inhaler?

It’s important that you know how to use your new inhaler in the best way to get the full benefits from it.

Ask your GP or asthma nurse to show you the best technique for your new device. You can also ask a pharmacist.

Sometimes it can take a few goes to find the right inhaler for you. There are lots of different types of inhalers and different techniques.

Watch our inhaler technique videos to find out how to use your new inhaler.

How long before I see the benefits of my new medicine or inhaler?

You may start seeing some benefits sooner than others. For example, if you’ve been having trouble sleeping, this might be something you notice improving quite soon.

If you and your GP or asthma nurse want to see an improvement in your symptoms and asthma attacks, it may take a few weeks to see the full benefits.

Keep a record of your symptoms

It can help to keep a symptom diary, and a peak flow diary if you have one, when you first start a new treatment. This can help keep a record of any improvements to your symptoms and what you feel able to do. These are good signs that your new medicine is working well.

It’s also a way to record any asthma symptoms you’re noticing after changing your medicines or inhaler.

You might need some time to get used to the change of treatment. You may feel like your symptoms don’t improve straight away, or may even get worse for a while, while you get familiar with the right technique of your new inhaler.


See your GP urgently if:

your asthma symptoms are getting worse, or you need to use your reliever inhaler three or more times a week.

Will my new medicine have side effects?

All medicines have possible side effects, but not everyone gets them. The patient information leaflet that comes with your new medicine will list all the possible side effects and how common they are.

You might be able to avoid some of the common side effects like a sore mouth or oral thrush with good inhaler technique, using a spacer, and rinsing your mouth out after using your inhaler.

Talk to your GP, asthma nurse, or pharmacist if you’re worried about any side effects from your new medicine. You can also speak to one of the respiratory nurse specialists on our Helpline.

Why does my usual medicine have a different name?

If you’ve been given a medicine which has a different name it might be because you’ve been given a different brand of your medicine. But the medicines, dose, and inhaler type should be the same.

  • The NHS sometimes uses other brands because they cost less, but work just as well, and contain the same active ingredients.
  • If you have changed the type of inhaler you’re using, and you need more help to use it correctly, talk to your GP or asthma nurse. It may be that you need more help with inhaler technique. Or they may be able to find another inhaler that suits you better. 

Why is my medicine or inhaler a different colour?

Inhalers can come in lots of different colours, from brown to purple to orange. Reliever inhalers are usually blue, but some are blue and white.

If your inhaler is a different colour, your GP may have prescribed another brand of your usual inhaler. Or you may have a different type of inhaler.

Ask your doctor, asthma nurse, or pharmacist if you’re concerned. They can reassure you that your new inhaler may look different but contains the same medicine you were using before. Or if it’s a different type of inhaler, explain what it is and how to use it.

Some tablets or capsules come in different colours, shapes, or sizes too.

How can I switch safely to a low-carbon, greener inhaler?

Changing from a metered dose inhaler (MDI) to a low-carbon, greener inhaler like a dry powder inhaler (DPI) works well for most people.

In fact, most people find dry powder inhalers easier to use than MDIs because it’s easier to get the technique right.

Switch safely to a green inhaler by:

  • making sure your GP or asthma nurse shows you how to use your new inhaler 
  • watching our inhaler technique videos
  • updating your action plan so you’re clear on what to do if your symptoms get worse or you have an asthma attack. For example, should you still use your MDI reliever in an emergency because it can be used with a spacer
  • having a follow-up appointment six to eight weeks later to check how you’re getting on
  • seeing your GP urgently if your symptoms are getting worse or you need to use your reliever inhaler three or more times a week
  • asking about switching back to your usual inhaler if you’ve given it a try and it doesn’t suit you.

What do I do with my old medicines and inhalers?

Take your old inhalers to your local pharmacy. They may be able to recycle them or dispose of them in an environmentally friendly way.

They can also dispose of any old or unwanted medicines safely.

Find out more about reasons why your medicines might change. 

Get advice on what to do if your medicines have changed.

You can get advice and support about changing medicines or inhalers by calling a respiratory nurse specialist on our Helpline, 0300 222 5800 (9am-5pm; Monday-Friday). Or you can WhatsApp them on 07378 606 728.


Last updated November 2021

Next review due November 2024

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